A bleeding disorder in babies so rare that it typically affects fewer than one in 100,000 is becoming more common in Tennessee because parents are refusing vitamin K injections at birth, according to pediatric specialists.

Since February, four babies with no signs of injury or abuse have been sent to Monroe Carell Jr. Children's Hospital at Vanderbilt with either brain hemorrhages or bleeding in the gastrointestinal tract. Dr. Robert Sidonio Jr., a hematologist, diagnosed them with vitamin K deficiency bleeding.

After discovering that all four had not received the preventive treatment, which doctors have been giving to newborns since the 1960s, he started making inquiries. Pediatricians told him parents are increasingly refusing consent because of concerns based on misinformation or the goal of having natural childbirths.

"These were all patients that were born at home or born in the hospital, but all had declined vitamin K," Sidonio said.

All four children survived, but the three who suffered brain bleeds face challenges.

"These are kids that end up having surgery to remove the large amount of blood out of their head or they would have died," he said. "It's early. It's only since February, but some of the kids have issues with seizure disorders and will have long-term neurological symptoms related to seizures and developmental delays."

The babies initially appeared healthy, then began bleeding weeks after their births once their tiny bodies had depleted what little vitamin K they had.

Dr. Anna Morad, a pediatrician at Vanderbilt, said years ago no one ever questioned the protocol of giving the vitamin injection the day a baby is born. These parents also typically refuse a hepatitis B vaccine, which is given to the babies to protect them from possible exposure from the mother. The doctors blame "debunked" studies -- reports that have not stood up to scientific scrutiny -- still floating around on the Internet that have linked vaccine ingredients to autism and vitamin K injections to leukemia.

"In about 2009 or 2010, we started noticing we were getting patients who were declining the vitamin K injection," Morad said. "At that point, we got a committee together and started working on a form to provide some education. In 2011, we started having parents sign the form to say they understood the risks of declining vitamin K. It was a handful of parents every once in a while. The percentages weren't alarming."

But in the past 12 months, there has been a "dramatically increasing rate" of parents refusing to consent, she said.

Dr. Eric Palmer, a neonatologist who practices at TriStar Centennial Medical Center, said he has also noticed the trend.

"Parents are refusing vitamin K injections for various reasons," he said. "They don't want their baby to have the pain of injection. They are concerned over possible preservatives in the vitamin preparation or their concerns are associated with certain illnesses or diseases long-term. These are not supported by science but certainly have made the rounds on the Internet."

The bleeding disorder is more prone to occur when mothers breast-feed after refusing the injections for their newborns, according to both Morad and Palmer. Formula is fortified with vitamin K, but not enough to provide effective prevention.

They both recommend that mothers exclusively breast-feed -- after allowing their newborns to get the vitamin K injections. Morad said mothers cannot eat enough green vegetables to make up for a deficiency. Palmer noted that oral vitamin K supplements given to babies have been shown not to be effective in preventing the bleeding disorder.

Sidonio, the doctor who first noticed the problem in Tennessee, says he worries about undocumented cases of the disorder going unreported.

"Having four cases since February just at Vanderbilt was a little bit concerning to me," he said. "Because of that, we have actually talked to the CDC and are sort of looking into this to see if this is an emerging problem."